Bitcoin can be the future bank all over the world. It might be similar value of World Bank.
Now a days there are so many big transactions are done with crypto currency. If people dont want to tell globally about their transactions they may use crypto in big number of amount in a single transaction, and nobody else can recognize that why and what they do transfer.
If there any kind of illegal activities involved in that transaction then if there is bitcoin bank exist over there then some kind of transactions may be stop by the bank.
In that case all the government make bitcoin bank in future, they will ask for all accounts details and the person who access the account. If all holders gives them details then it will be it safe or not?
I do not think bitcoin banks are necessary. Bitcoins are a digital currency so how would banks help us in storing bitcoins. They would need large cold storages in order to store bitcoins of the peoples but it is not really necessary.
We peoples can use and store bitcoins so why do we need to rely on banks?